On 06/08/2009, at 4:55 PM, Joseph Wright wrote: > Suggestion (2): > > - o = standard optional LaTeX argument with no default value. > - d = delimited optional argument where both the delimiters and > default > must be given. > - b or n = optional braced argument (now have a choice!). I'm more in favour of having the single letter with a possible optional default. I still think that { o } and { o{default} } make the most sense. > This means that "o" is a shortcut for "d[]{\NoValue}", and that any > other case is handled "in full" using d. This seems like a reasonable > balance between making simple optional arguments easy and having a > consistent syntax: > > \DeclareDocumentCommand \foo { o m } { } > \DeclareDocumentCommand \foo { d[]{Stuff} m } { } > \DeclareDocumentCommand \foo { d(){0,0} m } { } % Optional co- > ordinates I like this way of doing coordinates. Could 'd{}{-default-}' be shoe- horned into this syntax as well? I suppose that would mean completely re-writing the parser. But then we wouldn't need another letter for my feature of limited value. Will